Parsons and Hillman, former members of the Byrds, founded the Flying Burrito Brothers in Los Angeles in 1968, appropriating the name from a group of local musicians who gathered for jam sessions. Earlier that year, Parsons had been the driving force behind the Byrds’ pioneering country rock album, Sweetheart of the Rodeo. The Burritos’ first album, The Gilded Palace of Sin (1969), also displayed Parsons’s guiding hand: he contributed most of the songs and shaped its combination of classic country and western—punctuated by Kleinow’s pedal-steel guitar—and hard-driving southern California rock. Even after Parsons left the Burritos in 1970 (replaced by Roberts), his songs continued to appear on the group’s albums, including the live Last of the Red Hot Burritos (1972), which also prominently featured bluegrass musicians. Numerous other personnel changes—including the arrival and departure of Leadon, who helped found the Eagles—and the group’s limited commercial appeal outside a small, devoted following contributed to its dissolution by 1973. Kleinow and Ethridge re-formed the band in 1975, and there were other short-lived incarnations into the 1990s.

Parsons is often called the originator of country rock. Although he disdained that moniker, his work provided the link from straight-ahead country performers like Merle Haggard to the Eagles, who epitomized 1970s country rock. Numerous performers have cited Parsons as a major influence, notably the singers Emmylou Harris (who collaborated with him in 1973) and Elvis Costello and the alternative rocker Evan Dando.